While not as fast as CoreI7 920's it is over 3 hours quicker than my ol P4c 3.2GHz system that was originally in this case and 13 mins faster than 64 bit. Got to love these quad cores _________________The BIGGER the GOVERNMENT, the smaller the citizen.

I run the funtoo git branch with core2 optimizations. More info about that here

My CPU is actually one of the rare unlocked versions of the QX9770, but I'm not certain that makes too much difference. The on-die caching is huge though, so this may have something to do with the performance..._________________-H0bb3z-
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Intel QX9770 | 6Gb DDR3 | ATI 4870 HD 1Gb | 2xSeagate 1Tb SATAs
Running Funtoo Core2 build

*whistle* That's a nice machine. That's 24 cores, lol. I don't think you'd have much compilation time on that, lol._________________Someone asked me once if I suffered from mental illness. I told him I enjoyed every second of it.
www.madchaz.com A small candle of a website. As my lab specs on it.

genlop keep track of what was build at what speed, so
- FEATURES="ccache" emerge -1 gcc && FEATURES="ccache" emerge -1 gcc FEATURES="ccache" emerge -1 gcc && FEATURES="ccache" emerge -1 gcc
This will lower your average gcc build time, let's say without ccache you need 2m to build gcc.
First run ccache take 2m30s, next run ccache cut down time to 1,30m: you end with
2,30+1,30+1.3+1.3=average build time for gcc will be 1m45s, without it, your gcc was taking 2m average time. A false "positive" result.
- same with FEATURES="distcc", will gave a false "positive" result,
- a previous cpu with your gentoo, emerge.log as record it's build time for gcc, now you are using a different cpu, but your previous emerge are still log and genlop have no way to know what gcc was build with the old cpu and what gcc was build with the new one. You can end-up with crazy values like 2 hours and 10 minutes, average 1 hour and 5 minutes to build gcc while your cpu will take 10 minutes only
So a false "negative" result

Yes, i didn't remove emerge.log since a long time, in fact i use gentoo for more than that, but i think i enable the emerge.log at that time and never removed it since.
- --jobs>1 will also produce a bad value. A false "negative" result. Let's see it.
time emerge --jobs=3 -1 vlc genlop gcc
real 9m10.649s
time emerge --jobs=1 -1 vlc genlop gcc
real 12m43.426s
(i don't use ccache else second run could have been lower, but i did the test with jobs=1 on 2nd to let everything possible help that run instead of the first one with jobs=3, disk caching...)
But why it will produce a false "positive" result so ?
Because using --jobs>1 will max out your cpu usage, lowering total time to build the 3 program, but higher total time tooked to build one, look at my genlop result after the 2 run.

If you compare first value is always higher than 2nd, but this was while using --jobs=3 and you finally end up with less time to build the 3 programs ?
Because 2nd value show all your cpu working on 1 program (and you might have cpu cores idle)
And 1st one show you cpu working 100% on 3 programs in parallel (and this time, as your cpu isn't 100% avaiable to build a program, it will need longer time to produce it). So instead of adding the 3 programs time, you should take the higest time took by the 3 programs to get the final result: here it was gcc with 9minutes 7seconds, close to the time result that was 9m 10s.
But genlop isn't aware of // tasking, and it will add the 3 time to produce it's estimated time, so worst than 12 minutes, genlop will base it on 9m10s+7m45s+7s = 16m45s

To sum up, even it's still far from perfect (program versions need different time to be build, disk/memory speed/size, tmpfs...), using genlop like this will produce a "better" result.
FEATURES="-distcc -ccache" emerge -1 --jobs=1 aprogram
and your last entry in "genlop -t aprogram" is the result of that last emerge.

and for the record, that computer who need 10 minutes to build its gcc, need "Estimated update time: 1 hour, 52 minutes." for the emerge -ep system | genlop -p test